Recent research at the Columbia-Presbyterian Medical Center, growing out of the preliminary studies of DeHirsch, Jansky & Langford (1966), Jansky & DeHirsch (1973) has produced a standardized test for dyslexia, the Rapid Automatized naming test (RAN). This test, developed by Denckla & Rudel (1974, 1976), utilizes a performance time score for speed of naming a standard sequence of items under time pressure. The test has successfully discriminated three group: a) dyslexics; b) non-dyslexic learning disabled; and c) normal controls. A concept of dyslexia in an aphasiological context underlies the work. Our laboratory specializes in the automated analysis of speech rhythms. The objectives of this project are: 1. To augment the single, overall time score on the RAN test (picture naming) with profiles of scores that identify the normal patterns of fluency and rhythmicity of the test performance; 2. To determine which of the profiles we have already derived from a previously diagnosed group of older dyslexics (8-11 yrs) will help to identify preschoolers and first graders at risk for serious reading difficulties later in school, permitting earlier, more effective remediation before secondary, irreversible psychological problems arise; 3. To identify distinctive early patterns in naming performance of preschool children that are predictive of subsequent reading difficulty in school among that same group.